2,068 research outputs found
Tractability of Theory Patching
In this paper we consider the problem of `theory patching', in which we are
given a domain theory, some of whose components are indicated to be possibly
flawed, and a set of labeled training examples for the domain concept. The
theory patching problem is to revise only the indicated components of the
theory, such that the resulting theory correctly classifies all the training
examples. Theory patching is thus a type of theory revision in which revisions
are made to individual components of the theory. Our concern in this paper is
to determine for which classes of logical domain theories the theory patching
problem is tractable. We consider both propositional and first-order domain
theories, and show that the theory patching problem is equivalent to that of
determining what information contained in a theory is `stable' regardless of
what revisions might be performed to the theory. We show that determining
stability is tractable if the input theory satisfies two conditions: that
revisions to each theory component have monotonic effects on the classification
of examples, and that theory components act independently in the classification
of examples in the theory. We also show how the concepts introduced can be used
to determine the soundness and completeness of particular theory patching
algorithms.Comment: See http://www.jair.org/ for any accompanying file
A Profile-Based Method for Authorship Verification
Abstract. Authorship verification is one of the most challenging tasks in stylebased text categorization. Given a set of documents, all by the same author, and another document of unknown authorship the question is whether or not the latter is also by that author. Recently, in the framework of the PAN-2013 evaluation lab, a competition in authorship verification was organized and the vast majority of submitted approaches, including the best performing models, followed the instance-based paradigm where each text sample by one author is treated separately. In this paper, we show that the profile-based paradigm (where all samples by one author are treated cumulatively) can be very effective surpassing the performance of PAN-2013 winners without using any information from external sources. The proposed approach is fully-trainable and we demonstrate an appropriate tuning of parameter settings for PAN-2013 corpora achieving accurate answers especially when the cost of false negatives is high.
Palliative care in long-term care facilities: a European perspective:Evaluating palliative care in cross-country quantitative and qualitative research
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Design Principles for Two-Dimensional Molecular Aggregates Using Kasha's Model: Tunable Photophysics in Near and Short-Wave Infrared
Technologies
which utilize near-infrared (700 – 1000 nm) and short-wave infrared (1000 –
2000 nm) electromagnetic radiation have applications in deep-tissue imaging,
telecommunications and satellite telemetry due to low scattering and decreased
background signal in this spectral region. It is therefore necessary to develop
materials that absorb light efficiently beyond 1000 nm. Transition dipole
moment coupling (e.g. J-aggregation) allows for redshifted excitonic states and
provides a pathway to highly absorptive electronic states in the infrared. We present aggregates of two cyanine dyes whose
absorption peaks redshift dramatically upon aggregation in water from ~800
nm to 1000 nm and 1050 nm respectively with sheet-like morphologies and high
molar absorptivities (e ~ 105 M-1cm-1). We use Frenkel exciton theory to extend
Kasha’s model for J and H aggregation and describe the excitonic states of
2-dimensional aggregates whose slip is controlled by steric hindrance in the
assembled structure. A consequence of the increased dimensionality is the
phenomenon of an intermediate “I-aggregate”, one which redshifts yet displays
spectral signatures of band-edge dark states akin to an H-aggregate. We
distinguish between H-, I- and J-aggregates by showing the relative position of
the bright (absorptive) state within the density of states using temperature
dependent spectroscopy. I-aggregates hold potential for applications as charge
injection moieties for semiconductors and donors for energy transfer in NIR and
SWIR. Our results can be used to better design chromophores with predictable
and tunable aggregation with new photophysical properties
Detecting Sockpuppets in Deceptive Opinion Spam
This paper explores the problem of sockpuppet detection in deceptive opinion
spam using authorship attribution and verification approaches. Two methods are
explored. The first is a feature subsampling scheme that uses the KL-Divergence
on stylistic language models of an author to find discriminative features. The
second is a transduction scheme, spy induction that leverages the diversity of
authors in the unlabeled test set by sending a set of spies (positive samples)
from the training set to retrieve hidden samples in the unlabeled test set
using nearest and farthest neighbors. Experiments using ground truth sockpuppet
data show the effectiveness of the proposed schemes.Comment: 18 pages, Accepted at CICLing 2017, 18th International Conference on
Intelligent Text Processing and Computational Linguistic
Effects of Fungicide Euparen Multi (Tolylfluanid) on Development of Preimplantation Embryos in Mouse
The effect of the fungicide Euparen Multi (containing 50% tolylfluanid) on the development of mouse preimplantation embryos was evaluated. Euparen Multi was daily administered per os to female mice (ICR strain) at four different doses of 118, 294, 588 and 1177 mg/kg b.m., beginning on day 1 of pregnancy. Embryos obtained on day 4 of pregnancy were stained by morphological triple staining (Hoechst 33342, propidium iodide, Calcein AM), and the number of nuclei, blastocyst formation, distribution of embryos according to the nucleus number and cell death incidence were determined. Embryos in the experimental groups (except for the lowest dose 118 mg/kg b.m.) showed a highly significant dose-dependent reduction in total cell numbers corresponding to the lower proportion of blastocysts. The occurrence of cell death was significantly increased in all experimental groups, indicating that Euparen Multi is able to cause cell death at relatively low doses. Our data demonstrate that Euparen Multi could induce significant alterations in the preimplantation embryo development
The inverse Laplace transform as the ultimate tool for transverse mass spectra
New high statistics data from the second generation of ultrarelativistic
heavy-ion experiments open up new possibilities in terms of data analysis. To
fully utilize the potential we propose to analyze the -spectra of
hadrons using the inverse Laplace transform. The problems with its inherent
ill-definedness can be overcome and several applications in other fields like
biology, chemistry or optics have already shown its feasability. Moreover, the
method also promises to deliver upper bounds on the total information content
of the spectra, which is of big importance for all other means of analysis.
Here we compute several Laplace inversions from different thermal scenarios,
both analytically and numerically, to test the efficiency of the method.
Especially the case of a two component structure, related to a possible first
order phase transition to a quark gluon plasma, is closer investigated and it
is shown that at least a signal to noise ratio of is necessary to
resolve two individual components.Comment: 13 pages (PostScript, including figures), BNL-NTHES
An Integrated XRF/XRD Instrument for Mars Exobiology and Geology Experiments
By employing an integrated x-ray instrument on a future Mars mission, data obtained will greatly augment those returned by Viking; details characterizing the past and present environment on Mars and those relevant to the possibility of the origin and evolution of life will be acquired. A combined x-ray fluorescence/x-ray diffraction (XRF/XRD) instrument was breadboarded and demonstrated to accommodate important exobiology and geology experiment objectives outlined for MESUR and future Mars missions. Among others, primary objectives for the exploration of Mars include the intense study of local areas on Mars to establish the chemical, mineralogical, and petrological character of different components of the surface material; to determine the distribution, abundance, and sources and sinks of volatile materials, including an assessment of the biologic potential, now and during past epoches; and to establish the global chemical and physical characteristics of the Martian surface. The XRF/XRD breadboard instrument identifies and quantifies soil surface elemental, mineralogical, and petrological characteristics and acquires data necessary to address questions on volatile abundance and distribution. Additionally, the breadboard is able to characterize the biogenic element constituents of soil samples providing information on the biologic potential of the Mars environment. Preliminary breadboard experiments confirmed the fundamental instrument design approach and measurement performance
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